Design of 1000-kV ultra-high voltage AC corona test cage in China

1000 kV ultra-high voltage (UHV) AC power transmission system is being constructed in China. UHV corona cage is an indispensable testing facility for the research of the electromagnetic environment problem caused by the corona effects of UHV transmission lines. In this paper, the principles for the selection of the key parameters of the UHV corona cage are analyzed in detail. According to the calculation results, the cross-section size of UHV AC cage is recommended to be 8 m times 8 m, and the length of the middle measuring and end shielding section, 25 m and 5 m respectively. Finally, a novel cage end structure is proposed for increasing the length of uniform surface gradients section.